<html>
<head>

<script>

function boom()
{
  var f = document.getElementById("f");
  var fd = f.contentDocument;
  fd.querySelectorAll("*");
  fd.documentElement.innerHTML = "3";
  document.body.removeChild(f);
}

</script>
</head>

<body onload="boom();"><iframe id="f" src="data:text/html,<html><head onfocus=2>"></iframe></body>
</html>
